The present invention relates to the field of electronic devices in general, and more particularly, to electronic devices and methods responsive to user proximity.
Many electronic devices, such as radiotelephones, include controls which may be used to operate the electronic devices. For example, a radiotelephone may include a keypad used to input information into the radiotelephone such as telephone numbers to be dialed.
Electronic devices may be used over a wide range of operating conditions. For example, radiotelephones may be used in conditions where the ambient lighting is dim. The radiotelephone may, therefore, have the capability to back-light the keypad to assist the user in seeing the keys more clearly in low-light conditions. More specifically, the back-light may illuminate the keys when the user pushes a button or otherwise invokes an operation of the radiotelephone.
Unfortunately, if the ambient light level is too low for the user to see the controls of the electronic device the user may push an incorrect control, thereby causing the electronic device to carry out an unintended operation or provide erroneous input. Once the controls of the electronic device are illuminated, the user may see the error and wish to correct it. The user may, for example, correct the error by deleting the erroneous input and providing the correct input. In view of the above, there is a need for improved interfaces of electronic devices and methods thereof.
In view of the above, it is an object of the present invention to allow improved electronic devices and related methods.
It is another object of the present invention to allow improved interfaces to electronic devices and related methods.
It is another object of the present invention to allow reduction in power consumption of electronic devices and related methods.
These and other objects of the present invention are provided methods and apparatus that illuminate keys of a keypad of an electronic device, such as a radiotelephone, when the proximity of a user to a sensor of the electronic device is less than a predetermined threshold. In particular, a processor of the electronic device controls operations of the electronic device. A keypad includes a plurality of keys, wherein the keypad provides keypad input to the electronic device when at least one of the plurality of keys is pushed. A sensor indicates the proximity of the user to the sensor, whereupon the processor determines the proximity of user to the sensor. When the processor determines that the proximity of the user to the sensor is less than the predetermined threshold, a light illuminates the plurality of keys, thereby improving the visibility of the keys. The sensor can be an infrared or capacitive sensor.
Accordingly, the keys of the electronic device can be illuminated without providing keypad input to the electronic device. For example, when a user""s finger is within a predetermined threshold distance, the keys of the keypad are illuminated in anticipation of the user wanting to use the keypad. The present invention, therefore, may avoid the need to push a key to illuminate the keys of the keypad, thereby allowing an improved interface to the electronic device for the user. Furthermore, the present invention may provide a reduction in power consumption by avoiding unneeded input simply to illuminate the keys so that the user can provide the intended input.
In a further aspect of the present invention, the light illuminates the keys when the processor determines that a user is in contact with at least one of the keys, wherein the contact between the user and at least one of the keys does not provide keypad input to the electronic device. For example, the light can illuminate the keys of the keypad when the user touches, but does not push, one key.
The sensor may include contacts on the keys and a comparator, electrically connected to the contacts, wherein the comparator provides a voltage level in response to contact with the user. The contacts can be made of a conductive material on the keys such as gold, silver, or copper.
In particular, the contacts can include first and second contacts on keys. The first and second contacts are electrically connected to each other in response to contact between the user and one of the keys. For example, the first and second contacts can be on the faces of the keys so that when the user touches a keyface, the first contact is electrically connected to the second contact which causes a detector to signal the processor that the user is touching a key.
In another aspect of the present invention, the light illuminates the keys when the processor determines that the user is in contact with at least two of the keys, wherein the contact between the user and the two keys does not provide keypad input to the electronic device. For example, the light can illuminate the keys of the keypad when the user touches, but does not push, two of the keys.
In a further aspect of the present invention, the keys of the keypad can be in one of two states: depressed and non-depressed. For example, when a key is pressed the key is in the depressed state and when the key is not pressed, such as when the radiotelephone is not being used, the key is in the non-depressed state. According to the present invention, input can be provided to the radiotelephone when a key is in the depressed or the non-depressed state. For example, input can be provided to the radiotelephone when the user depresses a key or when the sensor detects proximity of the user. As a result, the present invention may allow, for example, increased input with fewer keys or allow the number of keys in the keypad to be reduced.
Detected contact by a user can also be used to initiate operations of the electronic device. For example, a radiotelephone that operates according to the present invention can detect contact between the sensor and the user""s face when the user places the radiotelephone near his or her ear. Accordingly, the contact may be used to answer the call rather than by pushing a button or opening a cover of the radiotelephone.